[ssl] dissect handshake messages even if we have no tree

this is to make sure that all expert info we see in the
main window will also appear in the expert info window

the sample capture from bug 11561 shows this problem:
without this patch, the expert info with severity 'error'
don't show up in the expert info window

Change-Id: Ia71ae7e248f57bf1344cf722ac57e74c517828d5
Reviewed-on: https://code.wireshark.org/review/11246
Petri-Dish: Michael Mann <mmann78@netscape.net>
Reviewed-by: Peter Wu <peter@lekensteyn.nl>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Michael Mann <mmann78@netscape.net>

1 files changed, 45 insertions, 47 deletions

diff --git a/epan/dissectors/packet-ssl-utils.c b/epan/dissectors/packet-ssl-utils.c
index 14fd94b2ec..487b31f304 100644
--- a/epan/dissectors/packet-ssl-utils.c
+++ b/epan/dissectors/packet-ssl-utils.c
@@ -5312,61 +5312,59 @@ ssl_dissect_hnd_hello_common(ssl_common_dissect_t *hf, tvbuff_t *tvb,
     guint8       sessid_length;
     proto_tree  *rnd_tree;
 
-    if (tree || ssl) {
-        if (ssl) {
-            StringInfo *rnd;
-            if (from_server)
-                rnd = &ssl->server_random;
-            else
-                rnd = &ssl->client_random;
+    if (ssl) {
+        StringInfo *rnd;
+        if (from_server)
+            rnd = &ssl->server_random;
+        else
+            rnd = &ssl->client_random;
 
-            /* save provided random for later keyring generation */
-            tvb_memcpy(tvb, rnd->data, offset, 32);
-            rnd->data_len = 32;
-            if (from_server)
-                ssl->state |= SSL_SERVER_RANDOM;
-            else
-                ssl->state |= SSL_CLIENT_RANDOM;
-            ssl_debug_printf("%s found %s RANDOM -> state 0x%02X\n", G_STRFUNC,
-                             from_server ? "SERVER" : "CLIENT", ssl->state);
-        }
+        /* save provided random for later keyring generation */
+        tvb_memcpy(tvb, rnd->data, offset, 32);
+        rnd->data_len = 32;
+        if (from_server)
+            ssl->state |= SSL_SERVER_RANDOM;
+        else
+            ssl->state |= SSL_CLIENT_RANDOM;
+        ssl_debug_printf("%s found %s RANDOM -> state 0x%02X\n", G_STRFUNC,
+                from_server ? "SERVER" : "CLIENT", ssl->state);
+    }
 
-        rnd_tree = proto_tree_add_subtree(tree, tvb, offset, 32,
-                                          hf->ett.hs_random, NULL, "Random");
+    rnd_tree = proto_tree_add_subtree(tree, tvb, offset, 32,
+            hf->ett.hs_random, NULL, "Random");
 
-        /* show the time */
-        gmt_unix_time.secs  = tvb_get_ntohl(tvb, offset);
-        gmt_unix_time.nsecs = 0;
-        proto_tree_add_time(rnd_tree, hf->hf.hs_random_time,
-                            tvb, offset, 4, &gmt_unix_time);
-        offset += 4;
+    /* show the time */
+    gmt_unix_time.secs  = tvb_get_ntohl(tvb, offset);
+    gmt_unix_time.nsecs = 0;
+    proto_tree_add_time(rnd_tree, hf->hf.hs_random_time,
+            tvb, offset, 4, &gmt_unix_time);
+    offset += 4;
 
-        /* show the random bytes */
-        proto_tree_add_item(rnd_tree, hf->hf.hs_random_bytes,
-                            tvb, offset, 28, ENC_NA);
-        offset += 28;
+    /* show the random bytes */
+    proto_tree_add_item(rnd_tree, hf->hf.hs_random_bytes,
+            tvb, offset, 28, ENC_NA);
+    offset += 28;
 
-        /* show the session id (length followed by actual Session ID) */
-        sessid_length = tvb_get_guint8(tvb, offset);
-        proto_tree_add_item(tree, hf->hf.hs_session_id_len,
-                            tvb, offset, 1, ENC_BIG_ENDIAN);
-        offset++;
+    /* show the session id (length followed by actual Session ID) */
+    sessid_length = tvb_get_guint8(tvb, offset);
+    proto_tree_add_item(tree, hf->hf.hs_session_id_len,
+            tvb, offset, 1, ENC_BIG_ENDIAN);
+    offset++;
 
-        if (ssl) {
-            /* save the authorative SID for later use in ChangeCipherSpec.
-             * (D)TLS restricts the SID to 32 chars, it does not make sense to
-             * save more, so ignore larger ones. */
-            if (from_server && sessid_length <= 32) {
-                tvb_memcpy(tvb, ssl->session_id.data, offset, sessid_length);
-                ssl->session_id.data_len = sessid_length;
-            }
-        }
-        if (sessid_length > 0) {
-            proto_tree_add_item(tree, hf->hf.hs_session_id,
-                                tvb, offset, sessid_length, ENC_NA);
-            offset += sessid_length;
+    if (ssl) {
+        /* save the authorative SID for later use in ChangeCipherSpec.
+         * (D)TLS restricts the SID to 32 chars, it does not make sense to
+         * save more, so ignore larger ones. */
+        if (from_server && sessid_length <= 32) {
+            tvb_memcpy(tvb, ssl->session_id.data, offset, sessid_length);
+            ssl->session_id.data_len = sessid_length;
         }
     }
+    if (sessid_length > 0) {
+        proto_tree_add_item(tree, hf->hf.hs_session_id,
+                tvb, offset, sessid_length, ENC_NA);
+        offset += sessid_length;
+    }
 
     return offset;
 }